Device preventing the backfire in internal combustion engines



Aug 0, 5- GIEYSSARTIER 2,012,000

DEVICE PREVENTING THE BACKFIRE IN INTERNAL COMBUSTION ENGINES Filed Sept. 10, 1932 v2 Sheets-Sheet 1 Fig.1 1 Fig.2

Aug. 20, 1935. G. EYSSARTIER DEVICE PREVENTING THE BACKFIRE IN INTERNAL COMBUSTION ENGINES Filed Sept. 10, 1932 2 Sheets-Sheet 2 Patented Aug. 20, .1935

* UNITED JSTATIEES PATENT [OFFICE DEVICE PREVENTING'THE BACKFIRE "IN INTERNAL COMBUSTION ENGINES Georges .Eyssartier, Arcachon, France Application September 10, 1932, Serial No. 632,616 In France October 8, 1931 r g 1 Claim.

I @My invention relates to a device securing a convenient protection against the danger of fire which may be produced byback fires in internal combustion engines of aerial and other vehicles for any use.

It has already been proposed, in order to prevent back fires tothe carburettor of internal combustion engines, to provide in the admission pipe.

one another by a sufiicient' space for leaving a convenient sectional areafor the passage of the fresh gases which feed the motor in normal operation of same. Said arrangement intended to prevent in an absolute manner the propagation of flames from the motor towards the earburettor thus securing the flight of the aircraft and, generally speaking, the normal operationof the internal combustion motors of any vehicle. 1 .I noticed that the actual construction of carrubettors, renders same sufiiciently tight and sufficiently prevents said carburettors'from being put in fire for instancethrough backfires, so that the protection of the vehicles upon which is located an internal combustion engine may be securedin a convenientmanner by locating groups of baffie's, not between the carburettor and air inlet, but between the 'carburettOr and engine,

thus efiiciently preventing flames'from going outof theair intake of the motor and thus suppressing any danger of fire cau sed by'a backfire from the motor.

The device according to my 7 invention thus comprises in combination with an admi'ssion. collector or pipe provided with an 'air intake for internal combustion engines baffles 'or groups of baffles in convenient contact with the wall of said intake or pipe'constituting' with said wall pock ets or receptacles turned towards the motor between thecarburettor andengine and the free ends of which join or cover each other in axial projection, said baffles being separated by suflicient intervals for securing in any condition the feeding in air of the motor without any danger of obstruction by freezing with a view thus to.

secure the normal feeding of the motor in any conditionof operation, while efiiciently preventingthe propagation outside of the vehicle of flames which could bring dangers of fire.

In the accompanying drawings which show'by 5 way of example preferred embodiments of devices according to my invention:-

Fig. l is a side view with parts in section ofv -a first constructional form diagrammatically of aircraft 0' shown of a device securing the safety during their flight against back fire.

Fig 2 shows amodification of Fig. 1, Fig. 3 shows byway of example a manner of securing the device upon anaircraft motor,- 3

Fig. 4 isadiagrammatical" view of a modifica- 1 tion'ofFig. 2, I

Fig. 5 shows a modification of Fig. 1,

Fig. 6 shows'a modificationv of Fig. 5, in which the pockets have a curved crosssectio'n; r Figs. "7 and 8 are views of the admission pipe 20 of Fig. 6 seen from the upper end andfrom the lowerend respectively.

Fig. 9 is a perspective view-of a member of Fig.6,

' Fig. 10 is a longitudinal section of an intake 25 pipe for aircraft,

Figs. 11 and 12 are views of 1O taken from the right end and from the left end of same respectively. I

Fig. 13 shows in cross section a perforation of the baffies of Fig. 10.

In the constructional; form of Fig. 1; the section of pipe I which is. to be connected through its flange 2'with the'usualintake air pipeof the carburettor not shown in the drawings, comprises bafile'sfi', solid with the wall of said pipe i by being cast with the same or secured on said wall by any means. Said baffles thus produce pockets 5, 6, a wallet" which is constitutedfor instance by the wall itself of the intake pipe I.

'In theconstructionalformof'Fig. 2, the pro,-

tecting device is constituted by lateral baflies 9 as in Fig. 1 and by means of central bafiies l.

The whole device. is designed for being located as shown in-Fig.'3 on the air intake of the car 4 burettor 8, said carburettor being of any known or approved'construction. H w I 'I'h'anks to this arrangement the air"feeding' of the motorwhich takes place in the direction of the arrows in Figs. 1 'and2, maybe effected nor- 0 mally inall conditions of operation of the motor, 3 the area of the cross section provided between the rows of bafiies 3, 4 or 1, 9, being sufficient for r securing a convenient passage of air for feeding the motor whatever may be the thickness of the any desired number. 1

ice which may have been deposited upon saidbaflles I, 9, owing to the atmospheric conditions, to the altitude of the flight or for any other reason.

Should a back fire to the carburettor take place, flames are arrested by the baffles which prevent said flames to be displaced in straight line while on another hand, the coolingof burning gases is efiiciently produced by the contact, on the one hand, with the wall of the air suction pipe I, which is in contact with the external air, and on the other hand, with the baflies which ends. Thanks to this arrangement, flames which occasionally come back from the motor are not permitted to make their escape out of the air intake pipe of the motor, so that any danger of fire of. the vehicle carrying the motor is practically avoided.

The number and arrangement 01" bail'les may be varied according to needs and according to particular circumstances of use, or according to the material of the device, said baffles being. in some cases provided with v perforations.

Said bailies may have a circular shape as in Fig. 6, or they maybe rectilinear and provided in In order to reduce the dimension of the in-,

.. dividual bafiles it is possible, as shown in Fig. 2,

to reduce the protruding of lateral baifies aby' providing inthe centrepart of the pipe divided bafiles, as shown in 3' in Fig. 4 17118 arrangement oi the whole device being of course-appropriate from the motor and whichtr-y to make theirescape outside along the direction shown by the arrow in Fig. 5.

As clearly seen in said Fig. 5, the several baflles I 9, l I, I2 are located a convenient distance apart for providing between said bafiies a cross section area suflicient for the passage of the air feeding themotor even when deposits of ice have taken place uponsaid bailles'. l

An efficient protection against fire causedby I back fires from, the motor, is thus realized while on another hand this arrangement avoids too smallcross section areas which would run the risk of beingobturated by ice.

Baffles may oirer any desired arrangement and be provided'in any number for preventing the passage of burning gases'coming from the motor while securing in any event the air feeding of the motor. l V

In Fig. 6 in which the number of bafiles has been increased in order to reduce the weight and dimensions of every bafile, pipe I shows a rectangular cross section as shown in Figs; 3 and 4, in order to render the construction easier and bafiles are constituted by kinds of half cylindrical gutters I3which are each constituted as shown inside pipe I.

in Fig. 9, by a half cylindrical tube provided at its ends with flanges '14 for securing said baffles Said flanges I4 may be secured upon the walls of pipe 1 for instance by riveting, soldering or otherwise thus securing an intimate contact of the ends of said baffles I3 with the v walls of pipe I.

Thanks to this arrangement, it is seen, as 7 shown by arrows F of Fig, 6, that the admission of air is effected by a sinuous course between the several baflles I3 which are located apart a sufficient distance for securing the passage of a are in contact with the pipe -wall at, least at their sufficient quantity of air even after a deposit of ice.

In the constructional arrangement of Figs.

to 12, the air intake pipe which is to be directly. located inside an aeroplane during the construction of same, directly receives bafiies I6 which are partially protruding upon each other, as shown in Fig. 10, said baffles being constituted by plates, which may be either solid or foraminated or which may be also constituted by groups of blades conveniently secured together, or by means of superimposed wire gauze. I

Intheseveralconstructional forms, the perforationswhich are provided in the several baffles,

could be preferably obtained as shown in Fig. 9, every perforation having awide base I! turned towards the arrival of air, followed by a narrowing chimney I8 which is obtained by a kind of stamping of the, material of said baiiie. Every chimney may have smooth edges as in Fig. 13, or said edges may be roughenedorconveniently cut or even. having fins ofyany desired direction.

The passage of gases in the reverse direction of arrows in Fig. 10, will be. prevented as long as said gases will be burning, said gases being cooled and extinguished during their passage through saidbafiles. H

Pipe I5 of Fig. 10 may have irustoconical shape as shown in this figure, or it may have a cylindrical shape, the cross section of said pipe being either circular, square, polygonal or having any other shape. v

The several airfeeding pipes such as I5, may of course have any orientation or direction, said pipes being either vertical, inclined or even horizontal or having an inclination from their upper to their lower end.

In the several forms of construction, the baffles may either be solidlwith the pipe which contains same or be secured inside side pipe by autogen soldering, rivetting or otherwise.

My invention applies for preventin'gdanger of fire due to back fires of internal combustion engines, more-particularly when said motors are located on any vehicle.

What. I claim is:.-

In an. internal combustion engine, an intake pipe for feeding the motor, transversal recti- 

